1. Field of the Invention
This invention relates to electrical switches in general, and more particularly to keyswitches in which the change in location of a permanent magnet causes the actuation of a sealed, magnetic responsive reed switch.
2. Description of the Prior Art
It is known in the prior art to control the closure or opening of electrical circuits with sealed reed switches which are responsive to the pressure of a magnetic field. Switches embodying this form of construction typically are characterized by a permanent magnet which is moved toward or away from a reed switch by hand actuation of a plunger mechanism. Some examples of prior known switches embodying this form of construction are disclosed in U.S. Pat. Nos. 3,233,061; 3,283,274; 3,292,123; 3,462,719; 3,465,271; 3,533,028; 3,559,124; 3,613,038; 3,622,926; 3,652,963; 3,652,964; 3,698,531; 3,736,397; 3,810,052; 3,921,108; and 4,117,430.
While switches constructed in accordance with the prior art provide a reliable means for opening or closing an electrical circuit, they are frequently difficult to assemble due to the need for the body of the reed switch to be accurately positioned relative to the direction of travel of the actuating magnet to insure consistent contact closure for a specified distance of travel of the magnet. Some prior known switches have insured that the reed switch remained correctly positioned relative to the path of travel of the actuating magnet by soldering the semi-rigid electrical contact leads of the reed switch to the body or to a rigid appendage of the keyswitch. While such forms of construction insure that the reed switch remains immobile relative to the path of travel of the magnet, the assembly of the keyswitch requires that the reed switch must first be properly positioned and then the switch leads must be soldered or otherwise rigidly fastened to the keyswitch to insure continued reliable operation of the mechanism. Such an arrangement also requires a separate operation to electrically connect the keyswitch leads to an external circuit.
Keyswitches are also known in the prior art in which the body of the reed switch is mounted in a vertical orientation. Switches of this form of construction are unsuitable for applications in which an easily assembled keyswitch is required which has a small overall height and which will actuate upon small movements of the permanent magnet.